ggg PSU pickup noise and Ferrite beads

[guavatone]

I just completed the  General Guitar Gadgets 4 output Isolated PSU with 2 transformers and putting it to use with a FF I built.  For some reason when my strat is on the neck and middle pickup I am getting High freq. noise -almost like white noise but mostly mids.  It doesn't do this with the battery.  Funny, usuallt the neck pickup is noisier.  Why is this happening -what could I do tofix it?

I put my AC on the PSU through a Ferrite ring, which is close to the transformers.  Maybe this is not good?  Is there a specific way to use these beads?  Do all the AC wires go through it?  I wasn't 100% sure on how to route through the bead.  I also added a ceramic .01 uF cap accross the AC input to cut down EMI/RFI.  

Thanks

[guavatone]

I just checked this symptom with my subescreamer and I don't get the same problem.  I have a feeling its the fuzz control pot that may be bad or maybe I need to add caps to the DC input at the pedal.


bump.....

[R.G.]

Some regulator chips oscillate if there is not a decoupling cap of about 01 - 22uF within an inch of trace from the input pin.

[guavatone]

I believe the ggg board has caps before and after the 78xx regulator 100uF before and 220uF after within one inch.  they are from + to - DC, I am not sure if that is considered decouling but I think it is.

I'ave been trying to figure out what makes a decoupling vs. bypass cap.  is it position in the circuit or function?  

Thanks RG, I love your site and visit it almost daily..... reguards.